A storage device usually refers to a disk array, is one or multiple disk devices which are used to store data and independent of a server, and includes a disk frame and multiple controller nodes. A current mainstream disk array uses a dual controller disk array. As shown in FIG. 1, the dual controller disk array includes two controller nodes and a disk frame, which is used for installation of a physical storage medium (for example, a solid state disk). Data in a server is stored in the disk frame through one controller node.
In an actual application, when one controller node in the dual controller disk array is invalid, the other controller node has to be capable of taking over data of the invalid controller node. In order to achieve the foregoing objective, a technical solution is proposed at present. In the solution, after a certain controller node is invalid, multi-path software running on the server detects a link state, and an invalid path (a data path 1 shown in a thin solid line in FIG. 1) is switched to a backup path (a data path 2 shown in a dotted line in FIG. 1), that is, the server switches a data transmission path of the invalid controller node to the other controller node, and re-sends data to be stored to the other controller node.
Although in the foregoing solution, a case that a certain controller node is invalid can be solved, the following problems exist: installing multi-path software provided by a storage device manufacturer in the server and using the software to perform path switching need to be implemented by performing a series of complicated configuration on the server and the disk array in advance, thereby increasing a redundant data amount of the server and the disk array.